Aerators molded in one piece are well known, for example, my U.S. Pat. Nos. 3,363,841, entitled Molded Water Aerators, granted Jan. 16, 1968, and 3,270,964, entitled Molded Water Aerator, granted Sept. 6, 1966, show all of the parts of an aerator, including the casting molded in one piece, except that the metal screens are separate and may be readily inserted into the molded aerator. It is desirable, however, in some cases, to use a metal casing for the aerator, and, consequently, there are a number of my prior patents which show such a casing with molded inserts capable of receiving a screen; see, for example, my U.S. Pat. Nos. 2,799,487 - "Aerator With Unitary Molded Inner Assembly", granted July 16, 1957; 2,998,929 - "Water Aerators", granted Sept. 5, 1961; 3,130,917 - "Water Aerator Having Improved Pre-Aerating Disc", granted Apr. 28, 1964; 3,130,918- "Slotless Aerator", granted Apr. 28, 1964; 3,270,965 - "Self-Sealing and Deposit-Proof Aerator", granted Sept. 6, 1966; British Pat. No. 1,189,550, published Apr. 29, 1970; Italian Pat. No. 854,515, granted Jan. 15, 1970; and French Pat. No. 1,596,242, delivered 15 June 1970. The aforesaid patents, however, do not disclose a one-piece insert capable of being molded at the lowest possible price and providing all of the advantages which an aerator is capable of providing. Very satisfactory aerators utilizing an imperforate cylindrical casing containing both metal and plastic parts are well known; see, for example, my U.S. Pat. No. 2,998,927 entitled "Fluid Mixing Devices", granted Sept. 5, 1961. These devices, however, do not have the cost-saving advantage of a single one-piece molded insert. Moreover, they do not have the advantage of a simplified assembly, nor do they have the advantage of ease of cleaning which allows the insert to be taken out, cleaned, and put back in the metal casing as is the case in my present invention.
It is, therefore, an object of my invention to provide such an aerator-adapted to be attached to the spout end of a faucet-which comprises a metal casing and a low cost one-piece insert for the casing.
It is another object of my invention to provide devices as set forth in the preceding object in which the aerating function is carried out with a very high degree of efficiency.
Still another object of my invention is to provide an aerator that overcomes any problem of leakage between the faucet and the aerator.
Yet an additional object of the invention is to provide an aerator which may not require a washer between the aerator and the faucet.
A further object of my invention is the provision of a plastic aerator insert formed in one piece, which is easily moldable and requires a minimum amount of plastic material.